This invention relates to an ink jet cartridge or cassette as used in an ink jet printer, more particularly to an ink jet cartridge which has a one-piece housing filled with ink and does not have a foam member. It will be appreciated, however, that the invention may find application in other applications and environments that encounter the same issues.
It is generally known in the art to form a cartridge housing or body having one or more cavities or chambers to hold a predetermined supply of ink. For example, a single color of ink may be provided into a chamber cartridge or multiple chambers may be provided, for example, each holding a different color ink stored therein for selective use in a printer.
It is also generally known to provide an ink absorbing member such as reticulated polyurethane or melamine foam that fits within one or more of the chambers. In some arrangements, the ink absorbing member fills the substantial entirety of the chamber, where in other instances a portion of the ink supply is free ink and the remainder of the ink is stored in the ink absorbing member. One or more outlet ports communicate with the respective one or more chambers through outlet passages. The outlet passage proceeds to a first or bottom wall of the housing. A supply needle from an associated printer extends through the outlet port and thus conveys ink from the housing to a recording head or a print head.
Typical ink jet cartridges are formed of a welded construction. The cartridge includes a housing and a lid or cover member welded onto the housing. The welding process adds time and expense to the manufacturing process of the cartridge. There is a need for a one-piece, homogeneous, integrally formed housing for an ink jet cartridge.
An ink absorbing member or foam is typically used as a resistive force to meter ink flow. There is, however, a need for an ink jet cartridge which does not use the foam reservoir. This allows use of pigmented ink in the cartridge which has an archival print. Foam reservoirs prevent the use of pigmented ink since the foam acts as a filter thus trapping pigment solid particles within the foam. A blow-molded single casing ink jet cartridge with a diaphragm-type venting mechanism would permit the use of pigmented ink. Thus, there is a need for a full liquid ink jet cartridge which does not have a foam reservoir to allow the use of pigmented ink in an ink jet printer.
The present invention provides an ink jet cartridge fabricated from a one-piece construction and fully filled with ink. More specifically, the ink cartridge includes a housing having a plurality of walls forming a top surface, a bottom surface, and side walls connecting the top and bottom surfaces. The walls form a chamber for receiving ink.
The housing is a one-piece, integral construction and is formed from a blow-molded plastic material. The housing is adapted to be fully filled with ink. In the preferred embodiment, the housing receives a pigmented ink. However, other inks may also be received by the housing.
An outlet passage extends from the bottom surface and communicates with the chamber and through which ink is selectively dispensed. A flexible seal is selectively attached to the outlet passage. A cap secures the seal to the passage.
A vent is formed on the top surface. The vent can include a porous member which is secured in the vent via a cap member. The porous member can have cell sizes which are adapted to allow air inflow to substantially equal ink outflow. The cap is a screw cap which is threadedly secured to the vent.
The vent can comprise a spring-loaded ball and cap assembly which secures the ball to the vent. Alternatively, the vent can comprise a diaphragm valve within the vent. The vent can also comprise a suction tube which extends from the vent opening to the bottom surface of the cartridge. A cap secures the tube to the vent opening.
A primary advantage of the invention resides in the housing being formed of a one-piece construction.
Another advantage of the invention relates to the ease of manufacture of the cartridge.
Still another advantage of the invention is found in the elimination of the foam member which reduces costs.
Yet another advantage is found in the ink cartridge which allows the use of pigmented ink.
Still yet further advantage resides in the ease and expense at which such improvements are achieved.
Still other aspects of the invention will become apparent to those skilled in the art upon reading and understanding the following detailed description.